
%0 Journal Article
%A Brown, RD 
%A Heffernan, ML 
%T The ' Variable Electronegativity ' Method. III. The Pyrrole Anion and Electronegativity Reversal
%J Australian Journal of Chemistry
%D 1959/09/01
%V 12
%N 3
%P 330-334
%K 
%R https://doi.org/10.1071/CH9590330
%U https://www.publish.csiro.au/paper/CH9590330 
%X The &#960;-electron distribution in the pyrrole anion has been evaluated by the VESCF method using two alternative methods of estimating core attraction terms. The results indicate that the &#960;-electron distribution around the conjugated system is very nearly uniform, supporting previous speculations that the relative attracting powers of tertiary nitrogen and carbon reverse when their &#960;-electron densities exceed a certain value, suspected to be not too much greater than unity. The present calculations indicate that the critical &#960;-electron density is around 1.2.  The VESCF estimates of ionization potentials of the pyrrole anion are also reported. 
